Mining conveyors



Dec. 31, 1957 e. DOMMANN MINING CONVEYORS Filed May 1?, 1953 INVENTOR GUNTHER DOMMANN.

BY @W DmKlnii ATTORNEYS United Sttes This invention relates to improvements in mining conveyors. It more particularly relates to an improved construction for a double-chain mining conveyor.

Double-chain mining conveyors are known which have two opposed side portions centrally joined by a bottom portion. Each of the side portions has a cross-sectional shape substantially approximating a W on its side. The two side sections are positioned so that the tops of the W face each other with the bottom portion of the conveyor joined as by welding to the apex of the central portion of each W cross-section. Continuous parallel scraper flights with each scraper joined at each end to a separate continuous chain are drawn by the chains along the top of the bottom section and return on the lower side of the bottom section. These flights of scrapers will cause the conveyance of a material such as coal, which is placed in the trough formed by the upper portions of the two side portions and the bottom portion. The flights of scrapers are driven by driving the chain to which they are connected, as, for example, by means of a sprocket wheel positioned at the end of the conveyor over which the chains pass and which in turn is driven by any suitable drive means.

The conveyor itself is composed of a multiple number of longitudinally extending connected sections. The sections are preferably so connected as to allow limited horizontal and vertical motion therebetween, so that the conveyor as a whole is somewhat flexible and may, for example, assume the contours of a mine floor on which it rests and a mine face along which it extends.

The conveyor is excellently suited for use in combination with a mining planer cutting head to form a mining planer machine. The conveyor is positioned along a longwall mine face and urged along its longitudinally extending length toward the mine face, as, for example, by pneumatic jacks. Due to its flexibility, it will, to a limited extent, assume the shape of the mine face. The planer head has two cutting edges for cutting in opposite directions and is somewhat in the form of a plough. it is drawn back and forth along the forward edge of the conveyor, and is usually guided with respect to the conveyor, as, for example, by means of a guide track or rail. As the planer is drawn back and forth, it will detach coal from the mine face and plough the same into the conveyor, which automatically conveys the same for removal by means of the flights of scrapers.

The use of a conveyor is, of course, not limited to the use in combination with the planer, but may be used for any conveying purposes in the mine.

The chains to which the flights of scrapers are attached and which actuate the scrapers move along the top of the bottom portion adjacent to each side portion and return on the under side of the bottom portion in substantially the same vertical plane.

In operation certain portions of the conveyor trough formed by the side bottom sections are subjected to much greater wear than other portions. The portions of the conveyor trough which come in contact with the moving atent O "ice chain to which the flights of scrapers are attached is, for example, subject to great wearing action. The portions of the trough immediately above and which come in contact with the returning chain have been found to be subject to a great deal of uneven wear. Since the conveyor is somewhat flexible, and will assume the shape of the mine floor, the same will be flexed downwardly when positioned over a depression in the mine floor. At the points where the conveyor is positioned over a depression and the same flexed downwardly, the portions of the conveyor immediately above the returning chain will press strongly against the chain and be subjected to great abrasive action by the chain. This results in a highly ununiform wear with these portions wearing to a much greater extent than the other portions. This uneven wear seriously weakens the conveyor and necessitates its replacement.

or repair.

One object of this invention is to overcome the abovementioned disadvantage. This and still further objects, will become apparent from the following description read in conjunction with the drawing, in which- Fig. 1 shows a cross-section of an embodiment of a double chain conveyor in accordance with the invention;

fig. 2 shows a top elevation of the conveyor shown in Fig. 1; and

Fig. 3 shows a cross-section of an embodiment of the connection of the bottom portion of the conveyor to a. side portion in accordance with the invention.

in accordance with the invention, the conveyor bottom has a thickened portion on its lower side above the chain. return where it is joined to the conveyor bottom portion.- This thickened portion will prevent the unequal wear to which the conveyor is subjected to, as pointed out above, from rendering the same useless, and will avoid expensive repairs.

Referring to the drawing, the two conveyor side portions 1 and 2 have the cross-sectional shape which approximates a W on its side. The portions are so positioned that the tops of the W face each other. The two side portions 1 and 2 are joined by the bottom portion 3, which is, for example, welded to the side portions. As can be seen from Fig. 2, the conveyor is composed of individually laterally extending joint sections 4 and 5. The sections 4 and 5 are so joined that a limited horizontal and vertical flexing may occur at the joints, which renders the conveyor as a whole somewhat flexible.

Two parallel chains 7 and 8 extend along the top surface of the bottom portion adjacent each side portion and return in a substantially vertical plane beneath the lower surface of the bottom portion. Regularly spaced apart and connected at each end to a chain are flights of parallel scrapers 6. The chains 7 and 8 are continuously driven, as, for example, by passing over a sprocket wheel at the end of a conveyor which is driven by a motor and move with them the flights of scrapers 6 which will convey coal or any other mineral deposited in the trough which is formed by the upper parts of the side portions and the top surface of the bottom portion.

In accordance with the invention, the underside of the connection of the bottom portion to the side portions above each chain return is thickened to take up the wearing action of the chain return. As shown in Fig. 1 the side portions of the conveyor are formed by two W-shaped irons which face each other and have the central apex 12. This apex has a thickened cross section as is shown at 12a. The free edges of the bottom portion 3 of the conveyor are welded to this projection at 9. The projection 12 has a greater thickness than the thickness of theconveyor bottom portion. The chains 7 and 8, respectively, on their return on the underside of the bottom por-- tion will, therefore, at the points of depression of the: trough bear on the surface 12a of the projections 12,

amends- 3 which are reinforced 'by their increased thickness. This will prevent premature wearing through of the conveyor trough at these points.

. The increase .incross-section of. the bottom portion adjacent to the side portion above the returningich ain, may be effected in any desired manner; The same may be in the form of a reinforcing strip attached as .by. welding to this portion. w p g It is possible to have each of the W-shaped irons forming the side portion ofthe conveyor formed from two separate U.-shaped portions. Such an embodiment is shown in Fig.3. The side portion with the W cross-section is formedfrom twou-shaped portions "15 and- "16. The portions at-which they are-joined, i. e., 15a and "16a, form a double thickness, which constitutes the thickened portion in a vertical direction above the returningch ain in accordance with the invention. If the portion 16a of the lower U-shaped portion 16 extends beyond the portion 15a, as shown by 16b, a suitable support for the conveyor bottom 3 is" formed on 16band the same may be welded in place at 18. The weld seam-for the welding of the conveyor bottom may act alone on combination with another weld such as the weld '17 to hold the individual U- shaped part profiles together for the formation of the W-shaped side portion iron. The welding may be effected as, for example, as a continuous welded seam or also by .spot welding at various points along the length.

In place ofthe chains, cables or any other flexible traction element may, of course, be used for moving the flights of scrapers.

I claim:

A double chain mining conveyor comprising twoopposed, spaced-apart side portions each of one piece consituation having substantially a W cross-sectional shape, the central apex of each side portion extending horizontally in the direction of the other side portion, a substantially horizontal bottom portion connected to each side portion at said apex to form a conveyor trough, said central apex having a greater cross-sectional thickness than said bottom portion and'forming an extension'of said bottom portion, a pair of parallel, spaced-apart endless flexible traction 'elerne'ntsone' movable longitudinally along the upper side of one of said apexes returning along the underside thereof and the other movable longitudinally along the upper side of the other of said apexes' aridreturning along the underside thereof, and parallel spacedapart flights of scrapers conhe'ctedat their ends between said flexible traction elements substantially transverse thereto.

References Gited in the file of this patent UNITED STATES PATENTS eb- 1 92 2,274,313 24, 2 04 16 Sept-25. 251. 2 5 02 re n-"+- 25 119. 2 2,702,697 'Lobb Feb. 22, 1955 FOREIGN PATENTS 12,148 Great Britain June '14, 1991 647,306 Gfeat'Br'itain Dec. 13,1950 843,678 Gei-iiia'ny July 10,1952 

